Texture models are potentially very useful for automated urban data revision. We propose a ‘model-based change detection algorithm’ using three-dimensional urban data. In this algorithm, temporal images are projected on a common three-dimensional geometry model and the latest textures are compared with previous textures to detect an object’s change accurately. In addition, a shadow simulation w...

This paper presents the design of a monocular vision based particle filter localization system for urban settings that uses aerial orthoimagery as the reference map. One of the design objectives is to provide a low cost method for outdoor localization using a single camera. This relaxes the need for global positioning system (GPS) which may experience degraded reliability in urban settings. The...

Reliable GPS positioning in city environment is a key issue: actually, signals are prone to multipath, with poor satellite geometry in many streets. Using a 3D urban model to forecast satellite visibility in urban contexts in order to improve GPS localization is the main topic of the present article. A virtual image processing that detects and eliminates possible faulty measurements is the core...

With the availability of very high resolution multispectral imagery from sensors such as IKONOS and Quickbird, it is possible to identify small-scale features in urban environment. Because of the multiscale feature and diverse composition of land cover types found within the urban environment, the production of accurate urban land cover maps from high resolution satellite imagery is a difficult...

This article presents a new approach for image segmentation applied to urban imagery. The proposed method is called re-segmentation because it uses a previous over-segmented image as input to generate a new set of objects more adequate to the application of interest. For urban objects such as roofs, building and roads, the algorithm tries to generate rectangular objects by merging and cutting o...

This paper demonstrates the use of High Dynamic Range (HDR) fisheye images of the sky dome in lighting simulations. The objective is to improve the accuracy of simulations with site specific sky conditions. The luminance information stored at a pixel level in an HDR photograph is used to light the simulated environment through an Image Based Rendering (IBR) technique. The results show that imag...

This paper presents the method to estimate the traffic flow on the urban roadway by using car’s on-dashboard camera image. The system described, shows something new which utilizes only road traffic photo images to get the information about urban roadway traffic flow automatically. Keywords—traffic flow estimation; on-dashboard camera; computer vision.

The feasibility to develop a rapid urban seismic damage detection procedure utilizing satellite radar imagery is investigated. In direct observation of city-wide building loss, remote sensing damage detection techniques have shown merits in rapid damage detection in urban areas. Remote sensing technology has the capability of extracting buildings in urban scenes. Comparing “before” and “after” ...

Brownfields, idle or under-utilized urban areas, were identified in three parts of the Phoenix metropolitan area using a supervised classification technique using ERDAS Imagine. The brownfields were first evaluated in an area of south Phoenix used as a control site to establish sample training sites. These sites provided the basis for the supervised classification of an ASTER satellite image, w...

Building extraction in urban areas is one of the difficult problems in image understanding and photogrammetry. Building delineations are needed in cartographic analysis, urban area planning, and visualization. Although one pair of images is adequate to find the 3D position of two visibly corresponding image features it is not sufficient to extract the entire building due to hidden features that...